PT-2026-37573 · Linux+3 · Linux+155

Published 2026-05-06 · Updated 2026-05-07 · CVE-2026-43233

Positive Technologies (AI Summary)

CVSS v3.1

8.2

High

Base vector

AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:H

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description An out-of-bounds read exists in the decode choice() function within the nf conntrack h323 helper of the netfilter component. The issue occurs because the boundary check before calling get len() uses an uninitialized len variable set to 0. When a bitstream is fully consumed, the check fails to prevent get len() from reading 1 to 2 bytes past the end of the buffer, leading to a heap-buffer-overflow read. This can be triggered remotely by sending a crafted Q.931 SETUP message containing a User-User Information Element with exactly 2 bytes of PER-encoded data to port 1720 through a firewall where the nf conntrack h323 helper is active.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Out of bounds Read

Weakness Enumeration

CWE-125

Related Identifiers

CVE-2026-43233

Affected Products

Linux

Linux-Allwinner-5.19

Linux-Aws

Linux-Aws-5.0

Linux-Aws-5.11

Linux-Aws-5.13

Linux-Aws-5.15

Linux-Aws-5.19

Linux-Aws-5.3

Linux-Aws-5.4

Linux-Aws-5.8

Linux-Aws-6.14

Linux-Aws-6.17

Linux-Aws-6.2

Linux-Aws-6.5

Linux-Aws-6.8

Linux-Aws-Fips

Linux-Aws-Hwe

Linux-Azure

Linux-Azure-4.15

Linux-Azure-5.11

Linux-Azure-5.13

Linux-Azure-5.15

Linux-Azure-5.19

Linux-Azure-5.3

Linux-Azure-5.4

Linux-Azure-5.8

Linux-Azure-6.11

Linux-Azure-6.14

Linux-Azure-6.17

Linux-Azure-6.2

Linux-Azure-6.5

Linux-Azure-6.8

Linux-Azure-Edge

Linux-Azure-Fde

Linux-Azure-Fde-5.15

Linux-Azure-Fde-5.19

Linux-Azure-Fde-6.14

Linux-Azure-Fde-6.17

Linux-Azure-Fde-6.2

Linux-Azure-Fde-6.8

Linux-Azure-Fips

Linux-Azure-Nvidia

Linux-Azure-Nvidia-6.14

Linux-Bluefield

Linux-Fips

Linux-Gcp

Linux-Gcp-4.15

Linux-Gcp-5.11

Linux-Gcp-5.13

Linux-Gcp-5.15

Linux-Gcp-5.19

Linux-Gcp-5.3

Linux-Gcp-5.4

Linux-Gcp-5.8

Linux-Gcp-6.11

Linux-Gcp-6.14

Linux-Gcp-6.17

Linux-Gcp-6.2

Linux-Gcp-6.5

Linux-Gcp-6.8

Linux-Gcp-Fips

Linux-Gke

Linux-Gke-4.15

Linux-Gkeop-5.15

Linux-Gke-5.4

Linux-Gkeop

Linux-Hwe

Linux-Hwe-5.11

Linux-Hwe-5.13

Linux-Hwe-5.15

Linux-Hwe-5.19

Linux-Hwe-5.4

Linux-Hwe-5.8

Linux-Hwe-6.11

Linux-Hwe-6.14

Linux-Hwe-6.17

Linux-Hwe-6.2

Linux-Hwe-6.5

Linux-Hwe-6.8

Linux-Hwe-Edge

Linux-Ibm

Linux-Ibm-5.15

Linux-Ibm-5.4

Linux-Ibm-6.8

Linux-Intel-5.13

Linux-Intel-Iot-Realtime

Linux-Intel-Iotg

Linux-Intel-Iotg-5.15

Linux-Iot

Linux-Kvm

Linux-Lowlatency

Linux-Lowlatency-Hwe-5.15

Linux-Lowlatency-Hwe-5.19

Linux-Lowlatency-Hwe-6.11

Linux-Lowlatency-Hwe-6.2

Linux-Lowlatency-Hwe-6.5

Linux-Lowlatency-Hwe-6.8

Linux-Lts

Linux-Nvidia

Linux-Nvidia-6.11

Linux-Nvidia-6.2

Linux-Nvidia-6.5

Linux-Nvidia-6.8

Linux-Nvidia-Lowlatency

Linux-Nvidia-Tegra

Linux-Nvidia-Tegra-5.15

Linux-Nvidia-Tegra-Igx

Linux-Oem

Linux-Oem-5.10

Linux-Oem-5.13

Linux-Oem-5.14

Linux-Oem-5.17

Linux-Oem-5.6

Linux-Oem-6.0

Linux-Oem-6.1

Linux-Oem-6.11

Linux-Oem-6.14

Linux-Oem-6.17

Linux-Oem-6.5

Linux-Oem-6.8

Linux-Oracle

Linux-Oracle-5.0

Linux-Oracle-5.11

Linux-Oracle-5.13

Linux-Oracle-5.15

Linux-Oracle-5.3

Linux-Oracle-5.4

Linux-Oracle-5.8

Linux-Oracle-6.14

Linux-Oracle-6.17

Linux-Oracle-6.5

Linux-Oracle-6.8

Linux-Raspi

Linux-Raspi-5.4

Linux-Raspi-Realtime

Linux-Raspi2

Linux-Realtime

Linux-Realtime-6.14

Linux-Realtime-6.17

Linux-Realtime-6.8

Linux-Riscv

Linux-Riscv-5.11

Linux-Riscv-5.15

Linux-Riscv-5.19

Linux-Riscv-5.8

Linux-Riscv-6.14

Linux-Riscv-6.17

Linux-Riscv-6.5

Linux-Riscv-6.8

Linux-Starfive-5.19

Linux-Starfive-6.2

Linux-Starfive-6.5

Linux-Xilinx

Linux-Xilinx-Zynqmp

Linux Kernel

References · 17

• https://git.kernel.org/stable/c/81f2fc5b0d0cf4696146f00f837596d10b92dead · Patch
• https://osv.dev/vulnerability/BELL-CVE-2026-43233 · Vendor Advisory
• https://git.kernel.org/stable/c/53d32735d77ab56cc3fc7bd53a7d099418f19be1 · Patch
• https://osv.dev/vulnerability/DEBIAN-CVE-2026-43233 · Vendor Advisory
• https://git.kernel.org/stable/c/bcb50aa0b8f2b74a9fe5a1c7bee6f2657a288041 · Patch
• https://nvd.nist.gov/vuln/detail/CVE-2026-43233 · Security Note
• https://security-tracker.debian.org/tracker/CVE-2026-43233 · Vendor Advisory
• https://git.kernel.org/stable/c/2a3aac4205e7d2f1aca2e3827de8cdd517d36c4a · Patch
• https://git.kernel.org/stable/c/baed0d9ba91d4f390da12d5039128ee897253d60 · Patch
• https://git.kernel.org/stable/c/7ef82863d42261817a6394c6c881bd6757a70f16 · Patch
• https://git.kernel.org/stable/c/35f1943d242e1b9f0b6e91c0c93bfb293a9f8224 · Patch
• https://git.kernel.org/stable/c/f0a83d0a4b7c127d32ac06d607a9214937716129 · Patch
• https://osv.dev/vulnerability/UBUNTU-CVE-2026-43233 · Vendor Advisory
• https://ubuntu.com/security/CVE-2026-43233 · Vendor Advisory
• https://cve.org/CVERecord?id=CVE-2026-43233 · Security Note